JPS61171887A - Enclosure type compressor - Google Patents

Abstract

PURPOSE:To reduce a surplus work quantity of a compressor through prevention of the occurrence of interference of a balancer with lubricating oil and to decrease the generation of noise, by a method wherein lubicating oil in a cover with high the balancer is covered can be discharged. CONSTITUTION:A balancer 8 is located to the lower end of a rotary shaft 6 of a vertical rotary type enclosure type compressor, and a cover 9, adapted to partition a balancer 8 from lubricating oil, is provided. A passage 24, having the one end open to the inner bottom part of the cover 9 and the other and open to the suction side 4b of a compressor part 3, is provided. A suction pres sure is exerted on the passage 24, and this causes discharge of lubricating oil gathering to the inner bottom of the cover 9.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a hermetic compressor, in particular a balancer is provided at the end of a rotating shaft of the compressor section, and a cover is provided around the rotating balancer. Concerning improvements in hermetic compressors.

[Technical background of the invention and its problems]

In a vertical rotary hermetic compressor, balancers are provided at the upper and lower ends of a rotor constituting a motor section, respectively, to eliminate unbalance during rotation. However,
This structure in which balancers are provided at the upper and lower ends of the rotor has the problem that a large inertial force is exerted around the rotor, and a large load is applied to the bearing section of the compressor section, which is coaxial with the electric motor section. When a large load is applied to a bearing, resistance increases accordingly, which not only increases power consumption unnecessarily but also tends to cause seizing of the bearing.

Therefore, as a bearing having a small mass and greatly reducing the load on the bearing, a bearing as shown in Japanese Utility Model Application Publication No. 58-75975 has been proposed.

As shown in FIG. 6, this is due to the rotation axis C of the compressor part placed inside the closed case a. In addition to providing a balancer e on the outer peripheral surface of the end on the oil d side, a cover f is provided around the balancer e to isolate the balancer e from the lubricating oil d, and the balancer e rotates within the cover f. The balancer i provided at the end of the rotor constituting the electric motor section Q is used to balance (offset) the amount of unbalance including the crank section j of the compressor section.

However, although such a structure does provide an effective balancing effect, it has the problem of increasing the amount of work the compressor does.

In other words, as shown in Fig. 7, with the cover provided on the compressor part, oil leaks from the gap between the rotating shaft C and the cover f, and the sliding parts are supplied with oil through the oil pump k of the rotating shaft C. r7aWI oil d after being removed falls into the camera bar f, and lubricating oil C accumulates inside the cover f. Moreover, the problem with farming is that it increases with the operation of the compressor. Therefore, at startup, although it works well for a while, when the lubricating oil d starts to accumulate inside the cover f and the amount increases, the balancer e rotates in the accumulated lubricating oil d, stirring up the lubricating oil d. Resistance valves add extra work to the compressor. As a result, the input to the compressor increases unnecessarily. Moreover, there is also the problem that the sound generated when stirring the lubricating oil d becomes a loud noise. In particular, these problems become more pronounced in inverter compressors that operate at high speeds by changing the operating hertz, and there is a need for something that can improve these problems.

[Purpose of the invention]

The present invention was made in view of the above-mentioned circumstances, and its purpose is to provide a compressor that can improve the input increase and noise caused by lubricating oil accumulated in the cover.

[Summary of the invention]

That is, this invention returns the lubricating oil accumulated in the cover to the suction side of the compressor by providing a passage whose one end opens to the inner bottom surface of the cover and the other end opens to the suction side of the compressor part. , which attempts to eliminate interference with the balancer's lubricating oil.

(R4, A□, ￥ This invention will be explained below based on an embodiment shown in Figs. 1 to 5. Fig. 2 shows the entire vertical rotary hermetic compressor to which this invention is applied. Fig. 1 shows the detailed structure of the lower part of the structure, where 1 is a sealed case in which lubricating oil 1a is stored in the inner bottom, 2 is a stator 2a and a rotor 2b.
A compressor section 6 is constructed by providing a main bearing section 5a and a sub-bearing section 5b on both sides of a cylinder 4 in which a roller 4a is rotatably housed so as to sandwich the cylinder 4 therebetween. is a hollow rotating shaft.

The electric motor section 2 is located on the upper side of the sealed case 1.
The compressor sections 3 are each installed on the lower side of the sealed case 1, and both are coaxially connected by a rotating shaft 6, so that the compressor section 3 can be driven using the electric motor section 2 as a drive source. It has become. Note that 6a is provided on the rotating shaft 6,
This is a crank portion for eccentrically rotating the roller 4a.

On the other hand, a balancer 7 is provided at the upper end of the rotor 2a. In addition, a balancer 8 that balances the balancer 7 and the crank part 6a is protruded from the outer circumferential surface of the end on the lubricating oil 1a side that protrudes from the sub-bearing part 5b of the rotating shaft 6. A cover 9 is provided from the outer periphery of the sub-bearing part 5 to the shaft end of the rotating shaft 6 so as to cover the balancer 7 and isolate the balancer 8 from the lubricating oil 1a, and the balancer rotates within the cover 9. 89
Balancer 7° crank part 6 that rotates together with the rotor 2a
From the three factors a, the unbalance of the entire compressor can be balanced without applying any load to the bearings 5a and 5b, as in the past (
offset).

It goes without saying that the outer peripheral part of the cover 9 is fixed to the sub-bearing part 5b, and the inner peripheral part is arranged so as not to impair the rotation of the rotating shaft 6. An oil pump 10 consisting of a groove portion 10a is provided on the inner surface of the rotary shaft 6, and is capable of supplying lubricating oil 1a to each sliding portion as the rotary shaft 6 rotates.

On the other hand, 20 is an oil return pipe disposed, for example, along the vertical direction on the outer circumferential side of the cover 9, and 21 is formed at a portion of the bottom wall of the cover 9 corresponding to the extension of the pipe 20. The recess 22 has an inner peripheral surface on the opening side of the recess 21,
The stepped portion 23 formed along the circumferential direction connects the cylinder 4 so that the suction hole 4b of the cylinder 4 communicates with the inside of the cover 9.
．． This is a through hole drilled in the sub bearing portion 5b. The oil return pipe 20 has a tip at its tip, as shown in FIGS. 3 and 4.
A narrow diameter portion 20a is formed with a narrow outer diameter. The tip of the small diameter portion 20a is inserted into the recess 21, and the rear end of the oil return vibrator 20 is inserted into the through hole 21.
3, and from the oil return vibe 20 and the through hole 23, there is a passage, which is the essential part of the present invention, and whose one end opens to the inner bottom surface of the cover 9 and whose other end opens to the suction side of the compressor section 3. It constitutes 24. Thereby, the lubricating oil 1a accumulated in the cover 9 can be returned to the suction side of the compressor. In addition, the narrow diameter portion 20a of the oil return pipe 20 has a stepped portion 20b formed at the base of the narrow diameter portion 20a as a stopper on the upper side. A shaped float 25 is provided so as to be movable in the vertical direction, and allows the opening of the recess 21 to be opened and closed. And in this 70-to 25,
A small hole 25a is provided along the direction in which the inside and outside of the recess 21 communicate with each other, and constitutes an oil amount control means 25b that changes the amount of lubricating oil 1a sucked in from the float 25. That is, when a large amount of lubricating oil 1a accumulates in the cover 9, the opening of the recess 21 is gradually opened as the float 25 rises, that is, the flow path area is expanded, and a large amount of lubricating oil can be returned. When the level of the lubricating oil 1a decreases, the opening of the recess 21 is gradually closed by the descending float 25, so that a small or trace amount of the lubricating oil 1a can be returned. Note that the return l when the opening of the recess 21 is opened to the maximum is set to be larger than the lubricating oil 1a that falls into the cover 9 after refueling.

Further, the bottom wall of the cover 9 is slightly inclined to be at the lowest position at the recess 21, so that even a small amount of lubricating oil 1a can be returned.

Now, in the hermetic compressor configured in this way, by energizing the electric motor section 2, the compressor section 3 is
The lubricant 4a is driven to rotate and performs compression operation, but with this operation, oil leaks from the gap between the rotating shaft 6 and the cover 9, and the lubricant 1a after being supplied with oil.
When the lubricating oil 1a falls into the cover 9, etc., the lubricating oil 1a gradually accumulates inside the cover 9, and this causes the balancer 8 to rotate due to the lubricating oil 1a, which increases the workload of the compressor. It is pointed out that

However, according to the present invention, the passage 24 is provided to suppress the oil level in the cover 9 from rising. That is, to explain the effect of suppressing the rise in the oil level, it is assumed that there is only a small amount of lubricating oil 1a in cover 9, and that lubricating oil 1a is flowing into recess 21. In this state, as shown in FIG. 4, the float 25 descends and the recess 21
The aperture is made smaller (or closed). When the compressor is started in this state, the suction pressure (negative pressure) of the compressor section 3 is applied to the passage 24 and returns the lubricating oil 1a in the cover 9 from the recess 21 to the suction hole 4b side. At this stage, since the flow path area is small, a small amount of the lubricating oil 1a is returned to the suction hole 4b. Then, with the start-up, the lubricating oil 1a supplied to the sliding parts falls into the cover 9.
L accumulates inside cover 9! As the amount of 181 oil 1a gradually increases and the oil level rises, the opening of the recess 21 gradually opens as the float 25 rises, and a large amount of lubricating oil 1a returns to the suction hole 4b due to the expansion of the flow path area. It will be done.

As a result, the amount of lubricating oil 1a inside the cover 9 gradually decreases. Then, by returning, the lubricating oil 1a inside the cover 9
When the oil level of
The lubricating oil 1a will be returned. And these lubricants 1
The return of a is repeated in the region below the balancer 8, suppressing the rise in the oil level of the lubricating oil 1a in the cover 9, and preventing interference between the balancer 8 and the 111W4 oil 1a.

Therefore, the balancer 8 in the lubricating oil 1a accumulated in the cover 9 causes extra work to be applied to the compressor.
rotation of the compressor can be prevented, and the input to the compressor can be reduced. Furthermore, since the balancer 8 does not stir up the lubricating oil 1a accumulated in the cover 9, there is no stirring sound and noise can be reduced. This effect is particularly significant in inverter compressors that operate at high speeds by changing the operating hertz.

In the above embodiment, the passage is provided inside the cover, but it goes without saying that the passage may be provided outside the cover.

In addition, in the above-mentioned embodiment, the oil amount control means for varying the amount of lubricating oil returned was configured using a float, but the invention is not limited to this, and other mechanisms, such as changes in the oil level. The oil amount control means may be configured using a level sensor that detects the lubricating oil and a solenoid valve that opens and closes in response to a signal from the level sensor to vary the amount of lubricating oil that returns.

Furthermore, although the present invention has been applied to a vertical rotary hermetic compressor, it is not limited thereto, and can of course be applied to, for example, horizontal or reciprocating compressors.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to eliminate interference between the balancer and the lubricating oil accumulated in the cover due to the lubricating oil returning to the suction side of the compressor section.

Therefore, it is possible to prevent the balancer from rotating within the lubricating oil, which causes extra work to be applied to the compressor, and it is possible to reduce the input power to the compressor.

Furthermore, since the balancer does not stir up the lubricating oil that accumulates inside the cover, there is no stirring sound and noise can be reduced.

[Brief explanation of drawings]

1 to 5 show one embodiment of the present invention.
The figure is an enlarged cross-sectional view showing the structure around the passage, which is the main part of this invention. Figure 2 is a cross-sectional view showing the overall structure of the hermetic compressor. Figure 3 is a float that constitutes the oil amount control means. 4th cross-sectional view showing the state in which the lubricant is rising and returning a large amount of lubricating oil.
The figure is a cross-sectional view showing the float descending and returning a small amount of lubricating oil, and Figure 5 shows the appearance of the float! Fig. 6 is a perspective view, and Fig. 6 is a sectional view showing a conventional hermetic compressor with a balancer installed at the end of the rotating shaft. Fig. 7 is a sectional view showing a conventional hermetic compressor with a balancer installed at the end of the shaft. It is a sectional view showing a state. DESCRIPTION OF SYMBOLS 1... Airtight case, 2... Electric motor part, 3... Compressor part, 6... Rotating shaft, 8... Balancer, 9...
Cover, 24... Passage, 25... Float, 25b
...Oil quantity control means.

Claims (2)

[Claims] (1) In a hermetic compressor in which a balancer is provided at the end of a rotating shaft of a compressor section disposed in a sealed case storing lubricating oil, and a cover is provided around the rotating balancer, one end is A hermetic compressor characterized by having a passage that opens at the inner bottom surface of the cover and whose other end opens on the suction side of the compressor section. (2) The passage is provided with oil amount control means for varying the amount of lubricating oil sucked from the passage depending on the level of lubricating oil accumulated in the cover. The hermetic compressor described in section.